Hi

When I try to build the following:

import std.algorithm.iteration;

void test(int[] array);

void main()
{
	int[] a = [1,1,2,2,3,3];
	foreach (p; a.permutations)
	{
		test(p);
	}
}

I get the error:

.\permutations_example.d(10): Error: function permutations_example.test(int[] array) is not callable using argument types (Indexed!(int[], ulong[]))
.\permutations_example.d(10):        cannot pass argument p of type Indexed!(int[], ulong[]) to parameter int[] array

What's the proper way to obtain the array of permutations of a?

Kind regards
David

On Sunday, 19 April 2020 at 17:57:21 UTC, David Zaragoza wrote:
> Hi
>
> When I try to build the following:
>
> import std.algorithm.iteration;
>
> void test(int[] array);
>
> void main()
> {
> 	int[] a = [1,1,2,2,3,3];
> 	foreach (p; a.permutations)
> 	{
> 		test(p);
> 	}
> }
>
> I get the error:
>
> .\permutations_example.d(10): Error: function permutations_example.test(int[] array) is not callable using argument types (Indexed!(int[], ulong[]))
> .\permutations_example.d(10):        cannot pass argument p of type Indexed!(int[], ulong[]) to parameter int[] array
>
> What's the proper way to obtain the array of permutations of a?
>
> Kind regards
> David

`permutation()` returns a lazy range (i.e an iterator). To turn a permutation into a concrete data type use .array on each one.

---
void test(int[] array){}

void main()
{
	int[] a = [1,1,2,2,3,3];
	foreach (p; a.permutations)
	{
		test(p.array);
	}
}
---

On Sunday, 19 April 2020 at 20:25:23 UTC, Basile B. wrote:
> On Sunday, 19 April 2020 at 17:57:21 UTC, David Zaragoza wrote:
>> [...]
>
> `permutation()` returns a lazy range (i.e an iterator). To turn a permutation into a concrete data type use .array on each one.
>
> ---
> void test(int[] array){}
>
> void main()
> {
> 	int[] a = [1,1,2,2,3,3];
> 	foreach (p; a.permutations)
> 	{
> 		test(p.array);
> 	}
> }
> ---

forgot to put the imports:

---
import std.algorithm.iteration, std.array;
---